Cancers are a leading cause of death in animals and humans. The exact cause of cancer is not known, but links between certain activities such as smoking or exposure to carcinogens and the incidence of certain types of cancers and tumors has been shown by a number of researchers.
Many types of chemotherapeutic agents have been shown to be effective against cancers and tumor cells, but unfortunately, many of these agents also destroy normal cells. Despite advances in the field of cancer treatment the leading therapies to date are surgery, radiation and chemotherapy. Chemotherapeutic approaches are said to fight cancers that are metastasized or ones that are particularly aggressive. Such cytocidal or cytostatic agents work best on cancers with large growth factors, i.e., ones whose cells are rapidly dividing. The exact mechanism for the action of these chemotherapeutic agents are not always known. Moreover, while some chemotherapeutic agents reduce the tumor mass significantly after one treatment, they unfortunately cannot be administered again to the same patient when the tumor returns as is usually the case. Some can only be administered once in a lifetime, others require several months or years delay between treatments.
Clearly, the development of materials that would target tumor cells due to some unique specificity for them would be a breakthrough. Alternatively, materials that were cytotoxic to tumor cells while exerting mild effects on normal cells would be desirable. It has been found that the benzimidazoles are especially effective in suppressing the growth of the cancers and tumors. The use of these benzimidazoles in sequential combination with other chemotherapeutic agents which are effective in debulking the tumor is a novel method of treatment. The preferred method involves first debulking or reducing the mass of the tumor with a cytotoxic agent and then administering the benzimidazoles.
It is an object of this invention to provide an anti-cancer therapy comprising a administering a chemotherapeutic agent first to reduce the mass of the tumor and then administering a benzimidazole derivative as defined herein to maintain or destroy the cancer. The agents may also be administered with the benzimidazole first and then the chemotherapeutic agent.
The benzimidazole can be administered in conjunction with a potentiator.
These and other objects will become evident from the following detailed description of this inventions.